1. Field of the Invention
This invention relates to a process for preparing condensates from phenolics and divinyl hydrocarbons. More particularly it concerns an improved process for preparing a condensate of phenol and divinylbenzene.
2. The Prior Art
It is shown in Hunt's U.S. Pat. No. 3,546,173 issued Dec. 8, 1970 that p-alkyl phenolic compounds and diolefinic hydrocarbons can be condensed in the presence of acidic catalysts such as boron trifluoride to yield polymer products. While the products of this prior process are similar to some of the products of the present process, the process itself has several major drawbacks. The acidic catalyst is not specific to ortho or para condensation of the phenolic so that if a phenol having hydrogen at its ortho and its para positions is employed, cross-linking alkylation at the ortho and para positions results to yield an intractable high molecular weight resin product. Also, as is expressly noted in the Hunt patent, this prior process requires a very pure diolefinic hydrocarbon feedstock, specifically one containing not more than 10% of nondiolefin impurities. Such a feedstock is extremely difficult to obtain. The diolefinic material is generally produced as a petroleum cut in which it is associated with mono-olefins, naphthas, and other hydrocarbons. Isolation by distillation is difficult at best because of the tendency of many diolefins to polymerize during distillation. It would be desirable and is an object of this invention to make available a process for forming essentially linear non-cross-linked soluble phenolic - diolefin polymers from economically attractive feedstocks.
It is a further object of this invention to provide a process for forming phenolic - diolefin polymers which employs low purity diolefin feedstocks.